Re: - VitA and Doxy photosensitivity

[Guest guest]

god. Learn something new every day. I didn't know about VitA and

sunburn- but I can tell you PABA the B vit works as good internally

as externally (it's in alot of suntan lostion).

I had a pretty bad case of photosensitivity to Doxy when I was on it

and wish I knew about VitA then... obviously no one on Lyme.net

knows.

How much per day did you take to have the redness remitt>

Barb

> Dear a

> Unfortunately Metronidazole is on the list as is Vitamin A

(which I was taking to reduce the photosensitization from Doxy)

> I've stopped taking both Mino and Doxy (and will stop the Vit

A as well). So far , no real change in headaches.

> The only surefire cure I can think of at this stage is a

headectomy :-).

> I'll keep you posted after my next visit to the duc.

> R

> [infections] Re: Intracranial

Pressure

>

>

> ,

> When I was hunting for causes of intracranial pressure I

found that mino and doxy can CAUSE it. I don't know about

metronidazole. Since I have taken so much Zithromax I looked to see

if there is any link with it. So far I have not found one. Are you

still taking mino or doxy?

>

> Like Tony, I would be hesitant to have surgery. So I am

looking for some other solution.

>

> One stopgap help I found is to put heat on my head during

the night. When I do this I am able to go back to sleep.

>

> a

>

> Dear Tony

> I'm glad that you were successful, mine is worsened by Mino,

Doxy and metronidazole.

> Regards

> R

>

[Guest guest]

I wonder why these vitamins help? Are the drugs depleting our natural stores or what? Does anyone understand the mechanism behind drug caused photosensitivity? pennyBarb Peck <egroups1bp@...> wrote: god. Learn something new every day. I didn't know about VitA and sunburn- but I can tell you PABA the B vit works as good internally as externally (it's in alot of suntan lostion).I had a pretty bad case of photosensitivity to Doxy when I was on it and wish I

knew about VitA then... obviously no one on Lyme.net knows. How much per day did you take to have the redness remitt>Barb> Dear a> Unfortunately Metronidazole is on the list as is Vitamin A (which I was taking to reduce the photosensitization from Doxy)> I've stopped taking both Mino and Doxy (and will stop the Vit A as well). So far , no real change in headaches. > The only surefire cure I can think of at this stage is a headectomy :-).> I'll keep you posted after my next visit to the duc.> R> [infections] Re: Intracranial Pressure> > > ,> When I was hunting for causes of intracranial pressure I found that mino and doxy can CAUSE it. I don't know about metronidazole. Since I have taken so much Zithromax I looked to see if there is any link with it. So far I have not found one. Are you still taking mino or doxy?> > Like Tony, I would be hesitant to have surgery. So I am looking for some other solution. > > One stopgap help I found is to put heat on my head during the night. When I do this I am able to go back to sleep.> > a> > Dear Tony> I'm glad that you were successful, mine is worsened by Mino, Doxy and metronidazole.>

Regards> R>

[Guest guest]

Penny:

Like everything chemical- it's complicated- but mainly because the

drug( saturates the tissues in the case of Doxy) absorbs ultraviolet

light.

Since SUNTAN LOTION also absorbs UV light (and re-emits it as heat)

I could never figure out why using sun block when you take DOxy

DIDN't work- at least not for me. I felt like I was on fire- and I

was taking the correct dose for my weight.

I kinda wonder if Vit A would have worked for me- If I'm on Doxy

again- I'll try it.

Barb

Drug Saf. 2002;25(5):345-72. Related Articles, Links

Drug-induced cutaneous photosensitivity: incidence, mechanism,

prevention and management.

DE.

Faculty of Pharmacy, The University of Sydney, Sydney, New South

Wales, Australia. demoore@...

The interaction of sunlight with drug medication leads to

photosensitivity responses in susceptible patients, and has the

potential to increase the incidence of skin cancer. Adverse

photosensitivity responses to drugs occur predominantly as a

phototoxic reaction which is more immediate than photoallergy, and

can be reversed by withdrawal or substitution of the drug. The bias

and inaccuracy of the reporting procedure for these adverse

reactions is a consequence of the difficulty in distinguishing

between sunburn and a mild drug photosensitivity reaction, together

with the patient being able to control the incidence by taking

protective action. The drug classes that currently are eliciting a

high level of adverse photosensitivity are the diuretic,

antibacterial and nonsteroidal anti-inflammatory drugs (NSAIDs).

Photosensitising chemicals usually have a low molecular weight (200

to 500 Daltons) and are planar, tricyclic, or polycyclic

configurations, often with heteroatoms in their structures enabling

resonance stabilisation. All absorb ultraviolet (UV) and/or visible

radiation, a characteristic that is essential for the chemical to be

regarded as a photosensitiser. The photochemical and photobiological

mechanisms underlying the adverse reactions caused by the more

photoactive drugs are mainly free radical in nature, but reactive

oxygen species are also involved. Drugs that contain chlorine

substituents in their chemical structure, such as

hydrochlorthiazide, furosemide and chlorpromazine, exhibit

photochemical activity that is traced to the UV-induced dissociation

of the chlorine substituent leading to free radical reactions with

lipids, proteins and DNA. The photochemical mechanisms for the

NSAIDs that contain the 2-aryl propionic acid group involve

decarboxylation as the primary step, with subsequent free radical

activity. In aerated systems, the reactive excited singlet form of

oxygen is produced with high efficiency. This form of oxygen is

highly reactive towards lipids and proteins. NSAIDs without the 2-

arylpropionic acid group are also photoactive, but with differing

mechanisms leading to a less severe biological outcome. In the

antibacterial drug class, the tetracyclines, fluoroquinolones and

sulfonamides are the most photoactive. Photocontact dermatitis due

to topically applied agents interacting with sunlight has been

reported for some sunscreen and cosmetic ingredients, as well as

local anaesthetic and anti-acne agents. Prevention of

photosensitivity involves adequate protection from the sun with

clothing and sunscreens. In concert with the preponderance of free

radical mechanisms involving the photosensitising drugs, some recent

studies suggest that diet supplementation with antioxidants may be

beneficial in increasing the minimum erythemal UV radiation dose.

> > Dear a

> > Unfortunately Metronidazole is on the list as is Vitamin A

> (which I was taking to reduce the photosensitization from Doxy)

> > I've stopped taking both Mino and Doxy (and will stop the Vit

> A as well). So far , no real change in headaches.

> > The only surefire cure I can think of at this stage is a

> headectomy :-).

> > I'll keep you posted after my next visit to the duc.

> > R

> > [infections] Re: Intracranial

> Pressure

> >

> >

> > ,

> > When I was hunting for causes of intracranial pressure I

> found that mino and doxy can CAUSE it. I don't know about

> metronidazole. Since I have taken so much Zithromax I looked to

see

> if there is any link with it. So far I have not found one. Are you

> still taking mino or doxy?

> >

> > Like Tony, I would be hesitant to have surgery. So I am

> looking for some other solution.

> >

> > One stopgap help I found is to put heat on my head during

> the night. When I do this I am able to go back to sleep.

> >

> > a

> >

> > Dear Tony

> > I'm glad that you were successful, mine is worsened by Mino,

> Doxy and metronidazole.

> > Regards

> > R

> >

>

[Guest guest]

Sun block doesn't work for me either. As soon as I get over this nasty cold, I'm going to see if I've got some A around the house. Paba too. If I've thrown them out, then I'll go buy some more. penny Barb Peck <egroups1bp@...> wrote: Penny: Like everything chemical- it's complicated- but mainly because the drug( saturates the tissues in the case of Doxy) absorbs ultraviolet light.Since SUNTAN LOTION also absorbs UV light (and

re-emits it as heat) I could never figure out why using sun block when you take DOxy DIDN't work- at least not for me. I felt like I was on fire- and I was taking the correct dose for my weight.I kinda wonder if Vit A would have worked for me- If I'm on Doxy again- I'll try it.BarbDrug Saf. 2002;25(5):345-72. Related Articles, Links Drug-induced cutaneous photosensitivity: incidence, mechanism, prevention and management. DE.Faculty of Pharmacy, The University of Sydney, Sydney, New South Wales, Australia. demoorepharm (DOT) usyd.edu.auThe interaction of sunlight with drug medication leads to photosensitivity responses in susceptible patients, and has the potential to increase the incidence of skin cancer. Adverse photosensitivity responses to drugs occur predominantly as a phototoxic reaction which is more immediate

than photoallergy, and can be reversed by withdrawal or substitution of the drug. The bias and inaccuracy of the reporting procedure for these adverse reactions is a consequence of the difficulty in distinguishing between sunburn and a mild drug photosensitivity reaction, together with the patient being able to control the incidence by taking protective action. The drug classes that currently are eliciting a high level of adverse photosensitivity are the diuretic, antibacterial and nonsteroidal anti-inflammatory drugs (NSAIDs). Photosensitising chemicals usually have a low molecular weight (200 to 500 Daltons) and are planar, tricyclic, or polycyclic configurations, often with heteroatoms in their structures enabling resonance stabilisation. All absorb ultraviolet (UV) and/or visible radiation, a characteristic that is essential for the chemical to be regarded as a photosensitiser. The photochemical and

photobiological mechanisms underlying the adverse reactions caused by the more photoactive drugs are mainly free radical in nature, but reactive oxygen species are also involved. Drugs that contain chlorine substituents in their chemical structure, such as hydrochlorthiazide, furosemide and chlorpromazine, exhibit photochemical activity that is traced to the UV-induced dissociation of the chlorine substituent leading to free radical reactions with lipids, proteins and DNA. The photochemical mechanisms for the NSAIDs that contain the 2-aryl propionic acid group involve decarboxylation as the primary step, with subsequent free radical activity. In aerated systems, the reactive excited singlet form of oxygen is produced with high efficiency. This form of oxygen is highly reactive towards lipids and proteins. NSAIDs without the 2-arylpropionic acid group are also photoactive, but with differing mechanisms leading to a

less severe biological outcome. In the antibacterial drug class, the tetracyclines, fluoroquinolones and sulfonamides are the most photoactive. Photocontact dermatitis due to topically applied agents interacting with sunlight has been reported for some sunscreen and cosmetic ingredients, as well as local anaesthetic and anti-acne agents. Prevention of photosensitivity involves adequate protection from the sun with clothing and sunscreens. In concert with the preponderance of free radical mechanisms involving the photosensitising drugs, some recent studies suggest that diet supplementation with antioxidants may be beneficial in increasing the minimum erythemal UV radiation dose.> > Dear a> > Unfortunately Metronidazole is on the list as is Vitamin A > (which I was taking to reduce the photosensitization from Doxy)> > I've stopped taking both Mino and Doxy (and will stop the Vit > A as well). So far , no real change in headaches. > > The only surefire cure I can think of at this stage is a > headectomy :-).> > I'll keep you posted after my next visit to the duc.> > R> > [infections] Re: Intracranial > Pressure> > > > > >

,> > When I was hunting for causes of intracranial pressure I > found that mino and doxy can CAUSE it. I don't know about > metronidazole. Since I have taken so much Zithromax I looked to see > if there is any link with it. So far I have not found one. Are you > still taking mino or doxy?> > > > Like Tony, I would be hesitant to have surgery. So I am > looking for some other solution. > > > > One stopgap help I found is to put heat on my head during > the night. When I do this I am able to go back to sleep.> > > > a> > > > Dear Tony> > I'm glad that you were successful, mine is worsened by Mino, > Doxy and metronidazole.> > Regards> > R> >>

[Guest guest]

Dear Barb

The Vit A I was taking are 5000 IU which equals 2750 micrograms of retinyl palmitate. I was on 2 a day. Hardly a lethal dose I had hoped.:-)

R

[infections] Re: Intracranial Pressure> > > ,> When I was hunting for causes of intracranial pressure I found that mino and doxy can CAUSE it. I don't know about metronidazole. Since I have taken so much Zithromax I looked to see if there is any link with it. So far I have not found one. Are you still taking mino or doxy?> > Like Tony, I would be hesitant to have surgery. So I am looking for some other solution. > > One stopgap help I found is to put heat on my head during the night. When I do this I am able to go back to sleep.> > a> > Dear Tony> I'm glad that you were successful, mine is worsened by Mino, Doxy and metronidazole.> Regards> R>

[Guest guest]

I found a billion papers on it in pubmed. All from the 1970s, so they

weren't online. I never looked em up in the med libe (and I'm not there

right now).

> Does anyone understand the mechanism behind drug caused

photosensitivity?

>

> penny